Average Co-Inventor Count = 1.68
ph-index = 6
The patent ph-index is calculated by counting the number of publications for which an author has been cited by other authors at least that same number of times.
Company Filing History:
1. Ppg Industries, Inc. (4 from 2,825 patents)
2. The Plessey Company Plc (3 from 36 patents)
3. Bicc Public Limited Company (1 from 105 patents)
8 patents:
1. 5955520 - Photochromic indeno-fused naphthopyrans
2. 5916943 - Method of marking an article
3. 5200116 - Photochromic chromene compounds
4. 4980089 - Photochromic spiropyran compounds
5. 4931221 - Photochromic spiropyran compounds
6. 4826977 - Photochromic spiropyran compounds
7. 4818096 - Photoreactive lenses with adamantane spiro compounds
8. 4737449 - Photochromic 3-pyrryl fulgides and fulgimides